Check engine light shorted?

[johnsTT]

I've got an 84 T-Type, and as soon as I key it on, or start it, the SES light goes on and does not go out. It doesn't even go out when I jumper the diagnostic terminal at the DLC. Any input would be appreciated.

 

[SLOW_85]

Diagnostic chart.
http://www.vortexbuicks-etc.com/start_trouble_shooting_here.htm

HTH

 

[johnsTT]

Thanks alot for the pinpoint tests. According to the results I have a defective ECM, because I have 2 PROMs that I tried with. Where would you suggest I get an ECM for a hot air car? Thanks again.

 

[johnsTT]

Hey guys, bad news. After replacing the ECM today the SES light will still not go out. I tried both PROMs again and still no change. The car has not been driven in about 6 months because I had to put a new transmission in it but I don't see what could have happened during the trans exchange or the wait in my garage. The car ran fine and the SES light worked properly when the trans went out. Any ideas would be appreciated. Thanks again.

 

[SLOW_85]

Will the car start and run?
If everything checked out,how did the ecm connections look?
Any corrosion?Chips seated properly?

 

[johnsTT]

The car starts and runs, but its really rich. I cant get a scan tool to comunicate but I did check O2 sensor output with a DVOM. The voltage stedilly climbs to about .965V and stays there. I introduced a vacumm leak to see if the reading would change and nothing. The PROM and the CALPACK chips seem to bee seated properly and there was no corrosion on the terminals.

 

[buickpower]

as far as the rich running goes, what are you running for static fuel pressure?



Also, do you have an 87 or 84 ecm?

 

[SLOW_85]

Since you had the tranny out,maybe you didn't get the grounds hooked back up.
Should be one on the bellhousing.
Sounds more like a ground/wire issue.

 

[johnsTT]

I'm pretty sure I put the bellhousing ground on, but I will check for sure. As far as the fuel system, everything is factory except for a walbro fuel pump and hotwire kit. My adj. fpr was leaking and replaced it with stock for now. Thanks for the help guys.

 

[johnsTT]

Oh, and it's still an 84 ECM.

 

[johnsTT]

Upon closer inspection, I don't have any grounds hooked up to the bellhousing bolts. However, I can't sem to find any unhooked grounds within the vicinity. Which of the bellhousing bolts should have a ground on them? Then I could narrow down the search.
Thanks, John

 

[SLOW_85]

Should be a braided line.
On my GN it's at the top and runs to the driver's side firewall.
Some people have it run to a head bolt.
Should also be a ground wire for the ecm.

 

[johnsTT]

The braided wire on the firewall is connected to on of my valve cover bolts but I still can' find another ground wire. Which harness does it come out of and where? Sorry for all the questions, this is just so frustrating. Thanks.

 

[SLOW_85]

Look on the troubleshooting link I gave you above.
On chart 2 shows the wiring diagram for the ALDL port/ecm.
Should be a ground from A12/CKT 450.
Kinda running out of ideas. If you do the troubleshooting step by step should determine the prob.
Look at the top of the page-hot air info sticky
It will have the ecm pinouts.
http://www.engraver1.com/help/ecm.gif
Also try a search on the board,maybe someone had a solution.

 

[johnsTT]

Thanks anyway.

 

[boosted84]

WHEN YOU SWAPPED OUT THE TRANS DID THE FOUR PRONG PLUG THAT PLUGS IN ON THE DRIVERS SIDE THAT CONTROLS LOCK UP PLUG IN OK. I HAD A PROBLEM SIMILAR TO THAT AND THE PLUG WOULDNT PLUG IN CORRECTLY TRANS COMPANY TOLD ME TO CUT NOTCHES SO IT WOULD FIT BUT THE CONVERTER WAS ALWAYS STAYING LOCKED UP. AT FIRST I THOUGHT IT WAS THE CHIP AND THE LOCK UP WAS BURNED WRONG BUT CHIP WAS FINE WIRE WERE JUST IN WRONG SPOTS JUST WONDERING CAUSE YOU SAID EVERYTHING WAS FINE TIL YOU DID THE TRANS SWAP GOOD LUCK KEEP US POSTED

ANTHONY

 

[johnsTT]

Hey guys, after rechecking the powers and grounds for the ECM, and reinstalling the factory PROM chip, I was able to pull a code 51-PROM Error. I went to reinstall my Ultrachip and found the PROM to be very hot to the touch. After installing the Ultrachip, code 51 has not come back and everything seems to be operating properly. Thanks for all the help everyone.